# File lib/phusion_passenger/debug_logging.rb, line 45
        def self.log_file=(filename)
                if filename && filename.empty?
                        @@log_filename = nil
                else
                        @@log_filename = filename
                end
                @@log_device.close if @@log_device && !@@log_device.closed?
                @@log_device = nil
        end